Apparatus for controlling the operation of domestic water systems



Sept. 8, 1953 A. P. BRUSH 2,651,259

. APPARATUS FOR CONTROLLING THE OPERATION OF DOMESTIC WATER SYSTEMSFiled May 20, 1949 2 Sheets-Sheet l INVENTOR. ALANSON anus FIG. 5.

ATTORNEY P 19 53 A. P. BRUSH 2,651,259

APPARATUS FOR CONTROLLING THE OPERATION OF DOMESTIC WATER SYSTEMS FiledMay 20, 1949 2 Sheets-Sheet 2- i I? 38 I I8 Y /z 75 V 62 L F76. 6 l as S64 73 f I x l4 INVENTOR. ALA/V80 R BRUSH Patented Sept. 8, 1953 UNITEDSTATES PATENT OFFICE APPARATUS FOR CONTROLLING THE OPER- ATION FDOMESTIC WATER SYSTEMS- Alanson P. Brush, Detroit, Mich. Application May20, 1949, Serial N 0. 94,407

other building removed from mimicipal water service facilities, withWater from a well, lake or stream. However, the method and apparatus ofmy invention may have other uses such as the pumping of liquids inindustrial plants in which case a pneumatic tank may or need not beemployed. The apparatus and method of my inven tion will be shown anddescribed in connection with the operation of both a deep well systemand a shallow well system since broadly the principles of my inventionmay be applied to both systems.

By a deep well system is meant one in which the jet pump of thejet-centrifugal system is located in the well, the distance from thenormal water level to the ground level being usually well in excess of33.9 feet (the theoretical practical limit of use of a shallow wellsystem). In adeep well system, two drop pipes extend down to the jetpump in the well, one for supplying water under pressure from thecentrifugal pump to activate the jet pump and draw water from the well,and the other the suction pipe through which water flows from the jetpump to the centrifugal pump. A shallow well system is one in which thedistance from the ground level to the water level is less than 33.9 feetbut allowances for losses and adequate margins of safety limittheapplication of a shallow well system to substantially less than thatdepth of well. In a so-called jet-centrifugal system which comprises thecombination of a jet pump and a centrifugal pump, the system isextremely'vulnerable for its efiicient and, in some cases, its continuedoperation to the presence of air in the system. This air may enter thesystem'in a number of difierent ways. It may enter the system throughleaks in the long lengths of piping which may extend 100 feet or moreinto the ground. Of course such leaks should be repaired as soon aspractical but often-times it is not convenient for the farmerimmediately to tear up the piping for repair. It is therefore, desirablethat the system be arranged so that it may at least temporarily functionto supply water until the farmer has time to shut itdown for repair.

9 Claims. (01. 1os

' above.

Another way in which air or gases enter the system is through or carriedby the'water being pumped; A significant portion of water wells containsgases or air, the amount thereof varying from Well to Well. Mostfrequenly the amount of air present is insufficient to causeconventional jet-centrifugal systems to discontinue their functioningalthough the presence of air or gas reduces the efiiciency of the jetpump, the centrifugal pump and the eificiency of the entire systeminsofar as its ability to pump its normal water capacity and develop itsnormal pressure.

In other wells, the quantity of air or gases present in the water beingpumped is suflicient to prevent the conventional jet-centrifugal systemfrom operating at all. In such cases the air drawn into the system withthe water being pumped accumulates in the system by reason of the factthat the air is not removed. This air recirculates back to the jet pumpthrough the pressure pipe and augments the air entering the system withthe water drawn from the well. The continuous accumulation of air in'the system without any adequate means for its disposal from the systemcauses the water to become aerated to an extent suflicient that thecentrifugal pump becomes air bound and ceases to function. Under suchconditions th jet-centrifugal system must be manually reprimed withwater.

Still another cause of air entering a jet-can trifugal system arises dueto the fact that in dry spells the water level in a great many wells Ifthe drought is of continued duration, the end of the suction pipe maybecome uncovered due to the fact that the capacity of the system drawswater from the well at a faster rate than water enters the well. Undersuch circumstances the end of the suction pipe may be uncovered for alength of time suflicient to draw enough air into the system to causethe centrifugal pump to become air bound and discontinue functioning.When the water level rises to an extent suflicient to again cover theend of the suction pipe, the

In the above discussion I have employed the expression conventionaljet-centrifugal system as meaning one in which no or inadequate means isemployed for disposing of the air which may enter the system in any oneof the ways described The term conventional jet-centrifugal system isnot intended to mean a system such as shown and described in Mann PatentNo. 2,257,507 issued September 30,1941. In that system means areprovided on the discharge side of drops.

for continuously removing air from the system; discharging that removedair into the pneumatic tank; and preventing it from recirculating backto the jet pump and accumulating in any substantial quantities likely tocause the system to become air bound. The method and apparatus of myinvention, unlike that shown in the above mentioned Mann patent, isdesigned to remove the air entering the system in any charge it from thesystem prior to its entry into the suction of the centrifugal .pump. Thesame above described considerations are also applicable to a shallowwell system although in .a :shallow well system the problems are not soacute.

An object of my invention is to method and apparatus adapted for bothshallow and deep well systems which is simple in construction andoperation and adapted to remove automatically from the system any airwhich may be drawn into the system before it has an opportunity to enterthe suction of thecentrifugal pump.

Another object of my invention is to provide a jet-centrifugal systemfor both shallow and deep wells which is reliable in operation and whichis designed to prevent any substantial amount of air which may get intothe system from circulating through the centrifugal pump andrecirculating to and through the jet of the jet pump to the end that thejet pump-and the centrifugal pump are maintained at maximum efficiency.

A further object of my invention is to provide a jet-centrifugal systemwherein means are provided on the suction side of the centrifugal pumpfor continuously removing such air as may enter the system to the endthat the centrifugal pump is at all times required to handle only waterfrom which substantially all the air has been removed whereby it willcontinuously function to maintain the system at full efiiciency, fullWater pumping capacity and full pressure regardless of whether air isentering the system; the system further being so constructed andarranged that if the quantity of air entering the system is extremelylarge, or if the supply of water from the well is entirely out 01f, thedischarge from the centrifugal pump to the pneumatic tank isautomatically closed so as to retain a body of water in the systemsufficient that-when water in sufficient quantities again enters thesuction pipe the system will automatically recover without any attentionon the part of the owner thereof and regain its ability to dischargewater into the pneumatic tank for use.

My invention further contemplates a jet centrifugal system in whichan'air separating ;chamber is employed on the suction side of thecentrifugal pump wherein air may separate from the water and bedischarged from the air separating chamber, the air separating chamberbeing provided with a float control arranged to actuate a valve locatedbetween the discharge of the centrifugal pump and the pneumatic tank;the valve being retained open when suf icient water is present in theair separating chamber and arranged to close automatically before thewater level in the air separating chamber drops to a level such that thecentrifugal pump is likely to draw air in any substantial quantitiesfrom the airseparating chamber, to the end that the system is completelyprotected and water will at all times be retained therein in sufficientquantities to maintain the system primed.

the centrifugal pump one of the ways mentioned above and dis-.

provide a novel Other objects and advantages of my invention will beparticularly pointed out in the claims and will be apparent from thefollowing description, when taken in connection with th accompanyingdrawings, in which:

Fig. l is a view largely diagrammatic of a deep well jet-centrifugalsystem having incorporated therein the novel apparatus of my iinventionand which is adapted to carry out my novel method of protecting thesystem from becoming air bound;

Fig. '2 isra-sectionalview taken substantially on .Fig. 3 is an enlargedsection of an air escape valve suitable for use with the novel apparatusof my invention;

Fig. are an enlarged sectional view of the float and the floatcontrolled valve adapted to close the delivery from the pump to thepneumatic tank or other po nt of us under certain conditions ofoperation;

Fig.5 is a top plan view of thevalve with the housing which contains it'being shown in section;

Fig. 'fiisa diagrammatic view-similarto Figq-l showing an arrangementwherein tl're princ'iples of my invention are incorporated in a shallowwell system; and

Fig. 7 is a plan view 'of a-portion-of Fig.6 showing the arrangement ofthe inlet and =outle't 'to the air separating chamber or air trap.

In the drawings I have shown (Fig. a centrifugal pump ll a jet pumpgenerally indicated by the numeral 12 and-a-pneumat-ictankiii-comprising the principal parts of a jet-centrifugal pumping system.These same principal parts are duplicated in the shallow well system ofFig. 6.

While I have 'shown'only the exterior casing of the centrifugal pumpsince centrifugal pumps are well known in the art, it need not b moreparticularly described. In general, the pump may be mounted with itsaxis of rotation horizontal or vertical and includes a suction I 4 and-adischarge H5. While I have shown a-centrifugal pump it will be-obviousthat other types-of-pumps may be employed. However, since the problem ofair handling by the pump and the effects of air getting into the systemis not serious inxconnection with a positive displacement pump, thisinvention .is primarily directed to such systems as-employ centrifugalpumpsorlother non-positive displacement types of pumps. A centrifugalpump will handle only limited '-quantities of allwithout losing itsprimeand-even limitedquantities of air seriously aifect its e'fficiencyand its ability to develop normal pressures.

The discharge of the centrifugal pump :is corn.

nected by :a :pipe 11 to the :pneumatic tank 1Z3 which may have anoutletifaucet .-i 8 and is usually.

connected by .an outlet '(not shown) :to the :house service lines. Anysuitable means (not shown) maybe rovided .for admitting airto the:system for the purpose of replenishing the air in the pneumatic tankand maintaining a sufficient quantity of air therein to provide -:thenecessary pneumatic cushion for forcing :the water under pressure fromthe pneumatic tank to the point of use.

.As shown .in-the drawings, the pipe I! is provided with a T :18preferably located adjacent the centrifugal discharge 126. .A pipe -2l:is con-- nected to the T and is adapted to convey part of the waterdischarged by the centrifugal .pump under pressure to the jet pump 12.

The jet pump 12 may be of conventional construction and comprises anozzle '22 and a diff'usrfl. As is well understood in theart, the

nozzle converts the pressure energy supplied to it by the centrifugalpump into velocity energy, a stream of water issuing from the tip of thenozzle at high velocity. The velocity of the stream creates asubatmospheric pressure in the space 24 adjacent the nozzle. Thepressure of air on the surface of water in the Well forces the water upthe well pipe 25 through a strainer 26 and a check valve 21 to satisfythe subatmospheric pressure existing in the space 24. The combinedstreams of liquid, that issuing from the nozzle 22 and that drawn fromthe well, flow through the mixing chamber 28 of the diffuser where thevelocities of the two streams are made more nearly uniform. The combinedstream then flows through the outwardly flaring portion of the diffuserwhere the velocity energy of the water is converted into pressureenergy. As is well understood in the art the pressure developed by thejet pump is added to that developed by the centrifugal pump to increasethe overall pressuredeveloped by the system, in some cases doubling thatpressure.

7 The water under pressure flows upward through a suction pipe 3i. Fromthe suction pipe the flow of water is through an elbow and nipple 32into an air separating chamber 33 or what might be termed an air trap.As shown at 30 (Fig. 2) the water enters the air separatingchamberpreferably in a tangential direction. Preferably at the bottom of theair separating chamber 33 an outlet 34 is provided which throughsuitable connections is connected to a suction pipe 36 which connectswith the suction l4 of the centrifugal pump. Preferably the outlet 34 isarranged tangentially of the air separating chamber. The tangentialinlet and outlet cause the water to rotate in the air separating chamberwhich tends to cause the water to seek the outer portions of the airseparating chamber while the lighter air tends to flow toward the centerof the air separating chamber and rise toward thetop thereof.

- Adjacent the entrance end of the air separating chamber 33, a bafilemay be provided, if desired, for the purpose of cutting down theturbulence in the air separating chamber which might be caused by thewater freely entering the chamber. Adequate air separation is dependentupon slowing down the velocity of liquid which in this case isaccomplished by the relatively large volume of the air separatingchamber 33 and by introducing the water into the air separating chamberin a manner such as to create as little turbulence as possible. Adequateair separation is further assisted by the rotary motion imparted to thewater as previously mentioned.

By employing an air separating chamber of relatively large volume,minimizing turbulence and circulating the water in the air separatingchamber, substantially all the air is removed from the water except suchair as may be held by the water in solution and such small amounts ofair as may be held in suspension. This separation occurs prior to thewater reaching the bottom outlet 34 from the'air separating chamber.Thus the water flowing to the suction I 4 of the centrifugal pumpthrough the pipe 36 is substantially air free, regardless of whether airis entering the system in one of the ways above mentioned.

For the purpose of removing air from the system on the suction side ofthe centrifugal pump and preventing it from passing thereto, I haveprovided the top of the air separating chamber: with suitable means forpermitting the escape.

nected into the top of the air separating chamher as shown at M. Thecasing has a generally cylindrical chamber 42 therein adapted to house afloat valve 43.

The float valve element 43 is adapted nor-' mally to seat upon, a valveseat, 46, the upper end of the valve element being partly spherical toprovide for accurate seating. The valve chamber has guides 41 withrespect to which the float valve is free to float by reason oftheclearance allowed and in accordance with the water level existent inthe chamber 42. The lower ends of the guides are turned inward toprovide a stop 45 for the float valve. Above the valve seat is a bore 48ber having a ball valve element 49 therein. The ball valve chamberexcept for an air escape passagej5l is closed by a plug 52. The lowerend of the plug 52 has a rib or ribs 53 to prevent the ball valveelement 49 from closing the air escape passage 5! Whenair even under aslight pressure enters the space beneath the ball valve element, theball is lifted to allow the escape of air to atmosphere through-thepassage 5!.

When the system is operating normally with little or no' air enteringthe system, the float valve 43 is maintained against its seat 46 due tothe float action of the float. If, however, any air is separated out inthe air separating chamber 33, that air rises and enters the floatchamber 42 and flows to the top thereof. With any substantial amount ofair in the float chamber, the float valve 43 lowers and leaves its seat.This action allows the air to escape until the water level againrises toclose the valve 43-46. Thus the valve 43-46 can be open only duringperiods when a volume of air is in the chamber 42 sufficient to causethe float valve 43 to leave its seat. As soonv as the chamber 42' isfilled with water the valve 43-46 seats and the system is tightly sealedagainst the escape of water. The air passing the valve 43-46 risesupward, opens the ball valve 49 and the air is allowed to escapeassuming a pressure above atmosphere in the air separating chamber.Whenever a'subatmospheric pressure exists in the. air separating chamberthe ball valve 49 is closed and prevents the entry of air into thesystem.

The'oondition illustrated in Fig. 3 is one during which air is enteringthe system. Under normal conditions of operation, when no air isentering the system in any one of the ways set forth above, the waterlevel will be above that shown and the water level will in fact extendup to the valve 43-46. The condition illustrated in the drawings is oneduring which relatively larg'ejquantities' of air are entering thesystem and the 'top of theair separating chamber up to the valve 43-46is filled with air separated from the water entering the system, throughthe suctionpipe. It will be noted that the valve 43-46 is open.

( Mounted in the air separating chamber is a float 62' which isconnected by a float stem 63 to a cylindrical valve 64. For this purposethe float stem 63 extends through an elongated slot which terminates ina ball valve chame.

shaped :opening ---.6.6:forn:led,-in 'adlxture 65 mounted in the wall:of the air separating chamber. The .fioat sstem extends :into :aval-ve:chan1ber 1. The float stem is threaded into the valve,as'indicated at '53. The valve 64 hasra thronghwater passage H.

The .air separating chamber .333 and the air handling capacity of 'the:air .nutlet 38 are sufficient in air separating and removingcapabilities to :take care of .most normal :conditions :aof operationincluding those encountered in a moderately aerated :origaseous well.That is, .the system will continuously operate with the centrifugal pumphandling substantially air free water andzth'e air being 'continuouslyremoved from the air separating chamber in the manner described above.

However, when abnormal well :conclitions are encountered as inthe caseof a -particu'lar'ly gaseous :well cr'under drought conditions, thewater level may be pumped to below the end of "the suction pipe so that:air or water mixed with air may enter the system. The air'may enter thesystem in such large quantities that it cannot be exhausted from the airseparating chamber-rapidly enough. Particularly under the lattercondition when air in considerable quantities is entering the suctionpipe, the water inthe air separating chamber 33 'will'be depleted andthe float 62 will drop. As the float drops, the valve 64 graduallythrottles the flow of water to the pneumatic'tank and when in its lowerposition, indicated in dotted lines, the flow of water to the pneumatictank is entirely cutofi.

The system is arranged so thatwhen the valve 34 closes sufficient volumeof water is :retained in the air separating chamber, the piping and inthe pump casing to maintain a body of liquid therein sufiicient so thata circulation of water through the system occurs. The valve is arrangedfor purposes of illustration so that it closes when moved throughapproximately 145 degreesat which point of closing'the 'air separatingchamber still retains "a substantial volume of water. That is, thecentrifugalpump-is"flooded and maintains a continuous circulationthrough the pipe 2-! down to the jet pump I72. fiow'of watercontinuously draws in air through'thefoot valve. This "air, as describedabove, is discharged through the air outlet. 'Since the discharge "ofwater from the system is 'cut off, a residual body of water ismaintained .in the system.

The air separating chamber 33 should be of sufiicientvolume to replaceany 'water'in thesystemthat has been lost :due to the ,foot valvebeingexposed'to atmosphere and-air entering the suction pipe. When thevalvefii closes and shuts off the flow to thepneumatic tank,.a body ofliquid should be retained in the system .tsufiicient in volume tomaintain the ipiping'full of water with circulation by the centrifugalpump still continuing. Under such "conditions the system willcontinuously .pump air and any water which may be available, dischargingthe air through the air outlet 38.

When theilow or liquid to thewell'returns to normal the valve willautomatically open and normal pumping will ,again be restored. Assumingthe how of water to the well .iscfsu'fiicient quantity, the air willgradually beeiihaustedfrom the air separating chamber 33, the float 62willrise and open the valve 63 at which time water will flow to thepneumatic tank. .Shoul-d the tend of the suction pipe be again exposed:to :air. as .is likely to occur during zaclrysp ll, the float 16.2 willagain .dro eto :close'the valve .64 and retain .a' body :of .liguid :inthe system sufiicient to insure starting or the system when the waterlevel again covers-the endroi the suction pipe. The only-condition whichmay arise which will require the attentionrof the operator that anextended dry spell result iii evaporation or the water in the :systemthus requiring that thesystem-be -.reprimed.

Eh-us the system is automatic in operation, being capable ofwithdrawing, without substantially any possibility :of failure, whateverflow-of water occurs into the well. :Moreover, regardless .of theconditions of operation, the flow of water to the centrifugalpumpissubstantiallyiair freeso :that'the efficien'cy of the centrifugal pumpis maintained. Moreover, the water flowing through the lpressurepipe itto the nozzle of the jet pump isalways substantially air .free so thatthat unit zis-m-aintained at its maximum efficiency.

.If, asisusualinzthe case of a dry spellthe-ilow of water into the wellis merely less than-the vfull capacity 10f the system, the system will.reach a condition of equilibrium in which the valve =64 inathrottlingjpositicn,throttledso as to-cut-down the new 10f water'to-thepneumatic tank to equal the flow of water into the-well. The system'willsupply to the pneumatictankall the water flowing into well without anyattention :on the part of the owner.

The above described conditions of operation may exist when very largequantities -of air enter the system. When an in smaller quantitiesenters the system, the system will discharge that air to atmospherewithoutrair-accumulatingin the air separating chamber in sufiicientquantities to :cause the float '62 to drop. This results from the fact:that air isdischarged from the air-separating chamber whenever apressure above :atmospher-eiexists therein. In any event, when thesystem stops under thecontrol of the usual pressure switchwith whichsuch systems are provided,

the pressures on opposite :sides of the centrifugal pump equalize andall air present is discharged fromwthe :air. separating chamber. Inother words, any air in the air separating :chamber is :dischargedtherefrom each time "the system cycles and the .fioat zdrops only underabnormal conditions of operation. As previously mentioned the valveduring closing throttles the discharge. If desired -this throttlingaction may be eliminated by=a snap action valve. If desired, .forexample, the float may be arranged to .open and :close contactwhichzenergizea solenoid. The solenoidin turn :controls itheva-lvefid.By this meansza snap action .oithe valve lid-maybe secured to avoid thethrottling effect above mentioned.

In the drawings :I;havessho.wn azpressure control valve 11.6 fm the"line between the discharge of (13b6, centrifugal pump and the valve'64. This valve is adapted :to beset for maintaining a'predeterminedtpressure of "water on the nozzle 22 :of the jet :pump :12. Itmay beofthe same construction as that shown in the ."Mann ipatent abovementioned, the valve being indicated in that patent-generally ibyi'bhe:numeral '39. The valve 16, as the corresponding valve of the Mannpatent, opens at a predetermined pressure and remains openras'ilongaszth'e pressure in the-system is above the setpoint'regardless ofwhether the .pump .is running or :not.

In Figs. 6 and '7, I have illustrated the application of my invention toa shallow well system. The function and ioperation of the centrifugalpump I l, the 'jet pump 12,, the pneumatic tank l3, the air separatingchamber 33, the air relief valve 38 and the valve 64 and its controllingfloat 62 are essentially the same as in the deep well system abovedescribed. However, in the shallowwell system no foot valve is required.A single pipe H extends into the well through which water is drawn from'the well. The jet pump I2 is located preferably above the centrifugalpump and water'flows from the diffuser of the jet pump through pipe 72into the air separating chamber. The nozzle of the jet pump receivespart of the water discharged by the centrifugal pump through a pipe 13.r

Preferably between the valve 64 and the pneumatic tank l3 a check valveis provided so that when the system reaches the shut off pressure andthe motor is stopped by the usual pressure switch, water from thepneumatic tank cannot back flow through the system to cause a drop inpressure in the pneumatic tank to atmospheric pressure.

The system is provided with a syphon breaker to prevent the draining ofthe water from the air separating chamber and the centrifugal pumpcasing when the pump is stopped. The syphon breaker may comprise a pipe15 extending into the pipe 13 which is in the form of an inverted U. Theother end of the U is formed with a valve seat upon which a ball valve11 seats to normally close the inlet to the pipe 15 when the system isoperating under pressure. When the system reaches shut-off pressure, thewater tends to drop down the suction pipe creating a subatmosphericpressure which opens the ball valve, breaks the syphon and prevents theair separating chamber and the centrifugal pump from being drained.

It will be noted that suction pipe H together with the air separatingchamber and the pipe 12 form a U loop on what may be termed a knee bendextending well above the level of the centrifugal pump. The syphonbreaker and knee bend protect the centrifugal pump and the air trap frombeing drained of water. In the shallow well system I have also shown apressure control valve 16 which, although not essential in a shallowwell system, is advantageous under some conditions.

The operation is essentially the same as in the deep well system exceptthat the necessity of employing a check valve in the line between thecentrifugal pump and the pneumatictank prevents the discharge of airfrom the air separating chamber each time the pump cycles. If acheckvalve is used'in the suction pipe the operation is identical.

While I have described my method of operat ing a jet centrifugal systemand have described an apparatus forcarrying out that method, it will beobvious that various changes may be madetherein particularly in the formand relation of parts without departing from the spirit of my inventionas set forth'in the appended claims. I

I claim: 1. A water system trifugal pump, a jet pump and a pneumatictank, said system having connections arranged so that water underpressure is supplied from the centrifugal pump to the jet continuouslywhen the system is in normal operation, water is drawn from the sourceof supply into the suction of the jet pump, the combined stream of waterflows from the. discharge of the jet pump tothe connected to a-sourceof' water supply comprising, in combination, a cenwater and in which airand centrifugal pump suction of the centrifugal pump and the waterdischarged by the centrifugal pump passes to the pneumatic tank exceptfor such water as is continuously recirculated to the jet of the jetpump, an air trap between the discharge of the .jet pump and the suctionof the centrifugal pump adapted normally to contain a substantial volumeof water and in which air and water separation may occur so that thewater supplied to the centrifugal pump is substantially air free, meansfor automatically releasing air from said air trap to atmospherecomprising a float valve having a seat against which it is normallypressed, a valve in the connection to the pneumatic tank from thedischarge of the centrifugal pump, and mechanical means in the air trapconnected to said second valve for closing said second valve when thewater in the air trap falls to a predetermined level. I

2. A water system connected to a source of water supply comprising, incombination, a centrifugal pump, a jet pump and a pneumatic tank, saidsystem having connections arranged so that water under pressure issupplied from the to the jet continuously when the system is in normaloperation, water is drawn from the source of supply into the suction ofthe jet pump, the combined stream of water flows from the discharge ofthe jet pump to the suction of the centrifugal pump and the waterdischarged by the centrifugal pump passes to the pneumatic tank exceptfor such water as is continuously recirculated to the jet of the jetpump, an air trap between the discharge of the jet pump and the suctionof the centrifugal pump adapted normally to contain a substantial volumeof water separation may occur so that the water supplied to thecentrifugal pump is substantially air free, means for automaticallyreleasing air from said air trap to atmosphere comprising a float valvehaving a seat against which it is normally pressed, a valve in theconnection to the pneumatic tank from the discharge of the centrifugalpump, a float in said air trap the position of which is determined bythe water level in the air trap, and a connection between said float andsaid second valve for progressively closing the second valve as thewater in the air trap drops.

3. A system as set forth in claim 2 wherein the water level in the airtrap when said valve is closed is above the level of the centrifugalpump and a syphon breaker is provided in the connection fromthe-centrifugal pump to the jet whichv opens when the pump stops toprevent draining of water from the air trap and the centrifugal pump.

4. In combination, a power driven water pump, a jet pump connected to asource of water supply,

aconnection from the discharge of said power driven pump to the jet ofsaid jet pump, an air trap for accumulating a substantial volume ofwater, a connection from the discharge of said jet pump to said airtrap, an air outlet valve for said air trap, a connection from said airtrap to the intake of said power driven pump for supplying said pumpintake with substantially air free water, a second connection from thedischarge of said power driven pump for delivering water therefrom,means including a valve in said second connection for preventingdelivery of water therethrough whenever a predetermined volume of airhas accumulated in said air trap until at least some of the accumulatedair in said air trap has been discharged through-the afore- 1 11 pump tosaid air trap,

I1 said air-outlet valve, apneumatic tank connected to said secondconnection, and a pressure control valve in said. second: connection formaintainingat least a minimum pressure on the jet of said; jet pump.

5. In combination, a power'drivenwater-pump, a jet pump connected to asource of water supply, a connection from the discharge of said powerdriven pump to the jet, of said jet pump, an air trap for accumulating asubstantial volume of water; a connection from the discharge of said anair outlet valve for said air trap, a connection from said air trap tothe intake of said power driven pump for supplying said; pump inta 'e;with substantially air free water, a second connection from thedischarge ofsaid power-driven pump for delivering water therefrom, avalve in; said second water delivery connection for preventing deliveryof water therethrough, means in said air trap connected tosaid valve forclosing said valve when a predetermined volume of air has accumulated insaid air trap, apneumatictank, and means between the discharge of thecentrifugal pump and said pneumatic tan for maintaining at least aminimum pressure on the jet of said 'j'et pump.

6. A water system connected to a source of water supply comprising,incombi'nation, a= centrif'ugal pump, a jet pump and a discharge foruse, said system having connections arranged so that water underpressure is supplied from the centrifugal pump tothe jet continuouslywhen the system is in normal operation, water is-drawn from the sourceof supply intothe' suction of the jet pump, the combined stream of"water flows from the discharge of the jet pump to the suction of thecentrifugal pump and the water-discharged by the centrifugal pump passestothe discharge for use except for such water as is continuouslyrecirculated tothe jet of" the jet pump, an air trap between thedischarge of the jet pump and the suction of the centrifugal pumpadapted normally to contain a substantial volume of water and in whichair and water separation may occur so that the water supplied to thecentrifugal pump is substantially-air free, an air outlet from said air'trap, afloat valve normally closing said outlet, a valve in thedischarge for use, and means in the air trap for closing said valve inthe discharge foruse when the water in the air trap falls-- to apredetermined level.

7; A domestic watersystem connected to a source of water supplycomprising; in combination, an intermittently operated centrifugal pump,a jet pump and a pneumatic tank, said system having connections arrangedso that water under pressure is supplied from the centrifugal pump tothe jet pump when thesystem is in normal operation, Water is drawn fromthe source of supply into the suction of the jet pump, the combinedstream flows from the discharge of the jet pump to the suction of thecentrifugal pump and the water discharged by the centrifugal pump passesto thepneumatietank except for such water as is continuouslyrecirculated to the jet pump, an air trap having ama-jorportion thereofabove the centrifugal pump and located between the discharge of the jetpump and the suction of the centrifugal pump and adapted normally tocontain a substantial volume of water and in which air and waterseparation may occur so that the water supply to the centrifugal pump issubstantially air free, an air release valve at the top of said trap,means formaintaining said release valve closed except when airfspresentin said air trap in an appreciable quantity whereby the systemoperates normally as a closed system and release of air occurs only atintervals when air enters the system with the water from the source ofsupply or through leaks insaid connections, a normally open valve in theconnection between the centrifugal pump and the pneumatic tank and meansin said airtrap for closing said normally open valve when air enters thesystem and a subatmospheric pressure exists in said" air trap, saidmeans closing said normally open valve before the water level in the airtrap falls below said centrifugal pump.

8 A domestic water system connected to a source of" water supplycomprising, in combination, an intermittently operated centrifugal pump,a jet pump and a discharge for use, said system having connectionsarranged so that water under pressure is supplied from the centrifugalpump to the jet pump when the system is in normal operation, water isdrawn from the source of supply into the suction of" the jet pump, thecombined stream flows from the discharge of the jet pump to the suctionof the centrifugal pump and the water discharged by the centrifugal pumppasses to the discharge for use except for such water as is continuouslyrecirculated to the jet pump, an air trap having a major portion thereofabove the centrifugal pump and located between the discharge of the jetpump and the suction of the centrifugal pump and adapted normally tocontain a substantial volume of water and in which air and waterseparation may occur so that the water supplied to the centrifugal pumpis substantially air free, an air release valve at the top of said trap,means for maintaining said release valve closed except when air-ispresent in said air trap in an appreciable quantity whereby the systemoperates normany as a closed system and release of air occurs only whena positive pressure exists in the air trap and at intervals when airenters the system with the water from the source of supply or throughleaks in said connections, a normally open valve in the discharge foruse, means in said air trap forclosing said normally open valve when airenters the system and a subatmospheric pressure exists in said air trap,said means clos ingsaid normally open valve before the water level inthe airtrap falls below said centrifugal pump, and a pressure control,valve in the dischargefor use, said pressure control valve being open solong as the pressure in, the system is above-a predetermined positiveminimum sothat when the pump stops the pressure in the, discharge foruse and the air trap will equalize and any accumulation of air in theair trap will be discharged therefrom.

9. In a water pump system the combination of a power driven water pump,a jet pump, a connection from the discharge of said. power driven waterpump to the jet of the said jet pump, a

.water supply normally exceeding the capacity of the pumping systemconnected to the intake of the said jet pump, said water supply havingno other connection to or association with the water pumping system, awater container adapted, to permit. the separation of air from the waterand being of sufficient; capacity to contain a. substantial volume ofseparated air and a considerable amount of substantially air free water,a connection from the discharge of the said jet pump to said water"container, a one way outlet device allowing air only to be forced out ofsaid water container, a connection from said water container to theintake of said power driven water pump for supplying said pump intakewith substantially air free water, a second connection from thedischarge of said power driven water pump for delivering water out ofthe said water pumping system, a valve in said second connec tion, meansfor closing said valve whenever a predetermined volume of air hasaccumulated in said water container whereby the entire delivery of waterfrom said power driven water pump passes through the jet of the jet pumpto prevent delivery of water out of said system and to increase thepressure in said water container to force at least a portion of saidaccumulated air out of said water container through said one way outletdevice, and thereafter reopen said valve to reestablish delivery ofwater out of said system.

ALANSON P. BRUSH.

Number 5 1,470,796 1,576,687 1,734,567 1,782,489 1,802,383 10 2,176,6582,257,507 2,433,021 2,486,288

Number Name Date Bachman Oct. 16, 1923 Thomas Mar. 16, 1926 Dunham Nov.5, 1929 Thomas Nov. 25, 1930 Jarvis Apr. 28, 1931 Gruman Oct. 17, 1939Mann Sept. 30, 1941 Bergh Dec. 23, 1947 Jacuzzi et al. Oct. 25, 1949FOREIGN PATENTS Country Date Great Britain 1932

